1
|
Munsters C, Siegers E, Sloet van Oldruitenborgh-Oosterbaan M. Effect of a 14-Day Period of Heat Acclimation on Horses Using Heated Indoor Arenas in Preparation for Tokyo Olympic Games. Animals (Basel) 2024; 14:546. [PMID: 38396514 PMCID: PMC10886293 DOI: 10.3390/ani14040546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Revised: 01/29/2024] [Accepted: 02/02/2024] [Indexed: 02/25/2024] Open
Abstract
To optimise the performance and welfare of horses during equestrian competitions in hot climates, it is advised to acclimate them to the heat. The effects of training in a heated indoor arena were studied. Four Olympic horses (13.3 ± 2.2 years; three eventers, one para-dressage horse) were trained for 14 consecutive days in a heated indoor arena (32 ± 1 °C; 50-60% humidity) following their normal training schedule in preparation for the Tokyo Olympic games. Standardised exercise tests (SETs) were performed on Day 1 and Day 14, measuring heart rate (HR; bpm), plasma lactate concentration (LA; mmol/L), deep rectal temperature (Trec; °C), sweat loss (SL; L), and sweat composition (K+, Cl- and Na+ concentration). The data were analysed using linear mixed models. The Trec and HR were significantly decreased after acclimation (estimate: -0.106, 95% CI -0.134, -0.078; estimate: -4.067, 95% CI -7.535, -0.598, respectively). Furthermore, for all the horses, the time taken to reach their peak Trec and heat storage increased, while their LA concentrations decreased. The SL, Cl-, and Na+ concentrations decreased in three out of the four horses. Conclusions: Fourteen days of normal training in a heated indoor arena resulted in a reduction in cardiovascular and thermal strain. This is advantageous because it shows that elite sport horses can be acclimated while training as usual for a championship.
Collapse
Affiliation(s)
- Carolien Munsters
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 114, 3584 CM Utrecht, The Netherlands (M.S.v.O.-O.)
- Equine Integration B.V., Groenstraat 2c, 5528 Hoogeloon, The Netherlands
| | - Esther Siegers
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 114, 3584 CM Utrecht, The Netherlands (M.S.v.O.-O.)
| | | |
Collapse
|
2
|
Verdegaal ELJMM, Howarth GS, McWhorter TJ, Delesalle CJG. Thermoregulation during Field Exercise in Horses Using Skin Temperature Monitoring. Animals (Basel) 2023; 14:136. [PMID: 38200867 PMCID: PMC10777899 DOI: 10.3390/ani14010136] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2023] [Revised: 12/24/2023] [Accepted: 12/26/2023] [Indexed: 01/12/2024] Open
Abstract
Hyperthermia and exertional heat illness (EHI) are performance and welfare issues for all exercising horses. Monitoring the thermoregulatory response allows for early recognition of metabolic heat accumulation during exercise and the possibility of taking prompt and effective preventative measures to avoid a further increase in core body temperature (Tc) leading to hyperthermia. Skin temperature (Tsk) monitoring is most used as a non-invasive tool to assess the thermoregulatory response pre- and post-exercise, particularly employing infrared thermographic equipment. However, only a few studies have used thermography to monitor skin temperature continuously during exercise. This commentary provides an overview of studies investigating surface skin temperature mainly by infrared thermography (IRT) during exercise. The scientific evidence, including methodologies, applications, and challenges associated with (continuous) skin temperature monitoring in horses during field exercise, is discussed. The commentary highlights that, while monitoring Tsk is straightforward, continuous Tsk alone does not always reliably estimate Tc evolvement during field exercise. In addition, inter-individual differences in thermoregulation need to be recognized and accounted for to optimize individual wellbeing. With the ongoing development and application of advanced wearable monitoring technology, there may be future advances in equipment and modeling for timely intervention with horses at hyperthermic risk to improve their welfare. However, at this point, infrared thermographic assessment of Tsk should always be used in conjunction with other clinical assessments and veterinary examinations for a reliable monitoring of the welfare of the horse.
Collapse
Affiliation(s)
- Elisabeth-Lidwien J. M. M. Verdegaal
- Thermoregulation Research Group, Equine Health and Performance Centre, University of Adelaide, Roseworthy, SA 5116, Australia; (G.S.H.); (T.J.M.); (C.J.G.D.)
- School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Roseworthy, SA 5371, Australia
- Research Group of Comparative Physiology, Department of Translational Physiology, Infectiology and Public Health, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| | - Gordon S. Howarth
- Thermoregulation Research Group, Equine Health and Performance Centre, University of Adelaide, Roseworthy, SA 5116, Australia; (G.S.H.); (T.J.M.); (C.J.G.D.)
- School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Roseworthy, SA 5371, Australia
| | - Todd J. McWhorter
- Thermoregulation Research Group, Equine Health and Performance Centre, University of Adelaide, Roseworthy, SA 5116, Australia; (G.S.H.); (T.J.M.); (C.J.G.D.)
- School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Roseworthy, SA 5371, Australia
| | - Catherine J. G. Delesalle
- Thermoregulation Research Group, Equine Health and Performance Centre, University of Adelaide, Roseworthy, SA 5116, Australia; (G.S.H.); (T.J.M.); (C.J.G.D.)
- Research Group of Comparative Physiology, Department of Translational Physiology, Infectiology and Public Health, Faculty of Veterinary Medicine, Ghent University, 9820 Merelbeke, Belgium
| |
Collapse
|
3
|
Poochipakorn C, Wonghanchao T, Huangsaksri O, Sanigavatee K, Joongpan W, Tongsangiam P, Charoenchanikran P, Chanda M. Effect of Exercise in a Vector-Protected Arena for Preventing African Horse Sickness Transmission on Physiological, Biochemical, and Behavioral Variables of Horses. J Equine Vet Sci 2023; 131:104934. [PMID: 37776920 DOI: 10.1016/j.jevs.2023.104934] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Revised: 09/14/2023] [Accepted: 09/23/2023] [Indexed: 10/02/2023]
Abstract
During an African horse sickness (AHS) outbreak, horses were able to exercise daily in a net-covered arena, yet the physiological responses to exercise in a netted arena was unknown. In a cross-over study design, eight horses performed a 39-minute aerobic exercise in conventional (CA) and vector-protected arenas (VPA). Horses were slower in some gaits and covered less distance in the VPA arena (P < .01). Cortisol release, hematology, and heart rate variability (HRV) were also examined. An interaction between the riding arena and time was observed in hematocrit (P = .0013), hemoglobin (P = .0012), and red blood cell count (P = .0027) and HRV variables, including mean beat-to-beat (RR) intervals (P < .0001), mean heart rate (P < .0001), sympathetic nervous system (SNS) index (P = .0038) and parasympathetic nervous system (PNS) index (P < .0001). Cortisol concentrations increased during exercise and 30 minutes postexercise in both arenas. Hematocrit, hemoglobin, and red blood cell count increased immediately postexercise in horses in VPA while remaining high from immediate post-exercise to 60 minutes postexercise in horses in CA. HRV decreased during exercise and was not different between horses in both arenas, but a higher RR interval and PNS index, corresponding to lower heart rate and SNS index, were detected during 30 to 60 minutes postexercise in horses in the VPA compared to the CA. Riding horses in different arenas impacted hematological and HRV variables. The greater RR intervals and PNS index, coinciding with the lower SNS index and heart rate, indicated parasympathetic dominance post-exercise in horses in VPA compared to CA.
Collapse
Affiliation(s)
- Chanoknun Poochipakorn
- Veterinary Clinical Studies Program, Faculty of Veterinary Medicine, Kasetsart University Kamphaeng Saen Campus, Nakhon Pathom, Thailand
| | - Thita Wonghanchao
- Veterinary Clinical Studies Program, Faculty of Veterinary Medicine, Kasetsart University Kamphaeng Saen Campus, Nakhon Pathom, Thailand
| | - Onjira Huangsaksri
- Veterinary Clinical Studies Program, Faculty of Veterinary Medicine, Kasetsart University Kamphaeng Saen Campus, Nakhon Pathom, Thailand
| | - Kanokpan Sanigavatee
- Veterinary Clinical Studies Program, Faculty of Veterinary Medicine, Kasetsart University Kamphaeng Saen Campus, Nakhon Pathom, Thailand
| | - Weena Joongpan
- Faculty of Veterinary Medicine, Rajamangala University of Technology Tawan-Ok, Chonburi, Thailand
| | - Pongphon Tongsangiam
- Faculty of Veterinary Medicine, Rajamangala University of Technology Tawan-Ok, Chonburi, Thailand
| | | | - Metha Chanda
- Department of Large Animal and Wildlife Clinical Science, Faculty of Veterinary Medicine, Kasetsart University Kamphaeng Saen Campus, Nakhon Pathom, Thailand; Thailand Equestrian Federation, Sports Authority of Thailand, Bangkok, Thailand.
| |
Collapse
|
4
|
Best R, Williams JM, Pearce J. The Physiological Requirements of and Nutritional Recommendations for Equestrian Riders. Nutrients 2023; 15:4977. [PMID: 38068833 PMCID: PMC10708571 DOI: 10.3390/nu15234977] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2023] [Revised: 11/26/2023] [Accepted: 11/28/2023] [Indexed: 12/18/2023] Open
Abstract
Equestrian sport is under-researched within the sport science literature, creating a possible knowledge vacuum for athletes and support personnel wishing to train and perform in an evidence-based manner. This review aims to synthesise available evidence from equitation, sport, and veterinary sciences to describe the pertinent rider physiology of equestrian disciplines. Estimates of energy expenditure and the contribution of underpinning energy systems to equestrian performance are used to provide nutrition and hydration recommendations for competition and training in equestrian disciplines. Relative energy deficiency and disordered eating are also considered. The practical challenges of the equestrian environment, including competitive, personal, and professional factors, injury and concussion, and female participation, are discussed to better highlight novelty within equestrian disciplines compared to more commonly studied sports. The evidence and recommendations are supported by example scenarios, and future research directions are outlined.
Collapse
Affiliation(s)
- Russ Best
- Centre for Sport Science & Human Performance, Waikato Institute of Technology, Te Pūkenga, Hamilton 3200, New Zealand
| | - Jane M. Williams
- Department of Animal Science, Hartpury University, Hartpury Gl19 3BE, UK;
| | - Jeni Pearce
- High Performance Sport New Zealand, Auckland 0632, New Zealand;
| |
Collapse
|
5
|
Shakeel M, Yoon M. Heat stress and stallion fertility. JOURNAL OF ANIMAL SCIENCE AND TECHNOLOGY 2023; 65:683-697. [PMID: 37970501 PMCID: PMC10640949 DOI: 10.5187/jast.2023.e29] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 01/25/2023] [Revised: 03/06/2023] [Accepted: 03/17/2023] [Indexed: 11/17/2023]
Abstract
The threat posed by increased surface temperatures worldwide has attracted the attention of researchers to the reaction of animals to heat stress. Spermatogenesis in animals such as stallions is a temperature-dependent process, ideally occurring at temperatures slightly below the core body temperature. Thus, proper thermoregulation is essential, especially because stallion spermatogenesis and the resulting spermatozoa are negatively affected by increased testicular temperature. Consequently, the failure of thermoregulation resulting in heat stress may diminish sperm quality and increase the likelihood of stallion infertility. In this review, we emphasize upon the impact of heat stress on spermatogenesis and the somatic and germ cells and describe the subsequent testicular alterations. In addition, we explore the functions and molecular responses of heat shock proteins, including HSP60, HSP70, HSP90, and HSP105, in heat-induced stress conditions. Finally, we discuss the use of various therapies to alleviate heat stress-induced reproductive harm by modulating distinct signaling pathways.
Collapse
Affiliation(s)
- Muhammad Shakeel
- Department of Animal Science and
Biotechnology, Kyungpook National University, Sangju 37224,
Korea
- Department of Clinical Studies, Faculty of
Veterinary and Animal Sciences, Pir Mehr Ali Shah, Arid Agriculture
University, Rawalpindi 44000, Pakistan
| | - Minjung Yoon
- Department of Animal Science and
Biotechnology, Kyungpook National University, Sangju 37224,
Korea
- Department of Horse, Companion and Wild
Animal Science, Kyungpook National University, Sangju 37224,
Korea
- Reseach Center for Horse Industry,
Kyungpook National University, Sangju 37224, Korea
| |
Collapse
|
6
|
Kang H, Zsoldos RR, Sole-Guitart A, Narayan E, Cawdell-Smith AJ, Gaughan JB. Heat stress in horses: a literature review. INTERNATIONAL JOURNAL OF BIOMETEOROLOGY 2023; 67:957-973. [PMID: 37060454 DOI: 10.1007/s00484-023-02467-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Revised: 03/21/2023] [Accepted: 03/28/2023] [Indexed: 06/15/2023]
Abstract
Healthy adult horses can balance accumulation and dissipation of body heat to maintain their body temperature between 37.5 and 38.5 °C, when they are in their thermoneutral zone (5 to 25 °C). However, under some circumstances, such as following strenuous exercise under hot, or hot and humid conditions, the accumulation of body heat exceeds dissipation and horses can suffer from heat stress. Prolonged or severe heat stress can lead to anhidrosis, heat stroke, or brain damage in the horse. To ameliorate the negative effects of high heat load in the body, early detection of heat stress and immediate human intervention is required to reduce the horse's elevated body temperature in a timely manner. Body temperature measurement and deviations from the normal range are used to detect heat stress. Rectal temperature is the most commonly used method to monitor body temperature in horses, but other body temperature monitoring technologies, percutaneous thermal sensing microchips or infrared thermometry, are currently being studied for routine monitoring of the body temperature of horses as a more practical alternative. When heat stress is detected, horses can be cooled down by cool water application, air movement over the horse (e.g., fans), or a combination of these. The early detection of heat stress and the use of the most effective cooling methods is important to improve the welfare of heat stressed horses.
Collapse
Affiliation(s)
- Hyungsuk Kang
- School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD, 4343, Australia.
| | - Rebeka R Zsoldos
- School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD, 4343, Australia
| | - Albert Sole-Guitart
- School of Veterinary Science, The University of Queensland, Gatton, QLD, 4343, Australia
| | - Edward Narayan
- School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD, 4343, Australia
| | - A Judith Cawdell-Smith
- School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD, 4343, Australia
| | - John B Gaughan
- School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD, 4343, Australia
| |
Collapse
|
7
|
Ebisuda Y, Mukai K, Takahashi Y, Ohmura H. Effect of high ambient temperature on physiological responses during incremental exercise in Thoroughbred horses. COMPARATIVE EXERCISE PHYSIOLOGY 2023. [DOI: 10.3920/cep220018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 03/19/2023]
Abstract
Several reports have suggested that the risk of exertional heat illness (EHI) in Thoroughbred racehorses increases in high ambient temperatures. Heat dissipation in horses during exercise becomes less efficient when the body temperature and ambient temperature are close. Therefore, we hypothesised that exercise at 40 °C may increase body temperature, oxygen consumption, and cardiac output during incremental exercise tests compared to 20 and 30 °C. Six trained Thoroughbred horses were studied in a randomised, crossover design at three ambient temperatures with a 6-day washout period. Using a 3% inclined treadmill, horses performed incremental exercise tests at 1.7, 3.5, 6, 8, and 10 m/s for 90 s at ambient temperatures of 20, 30, and 40 °C. The effects of ambient temperature at 10 m/s on physiological variables were analysed using mixed models (P<0.05). Pulmonary arterial temperature and rectal temperature at 40 °C were higher than those at 20 °C (P<0.001) and 30 °C (P<0.001). Similarly, oxygen consumption (vs 20 °C, P=0.009; vs 30 °C, P=0.006) and cardiac output (vs 20 °C, P=0.001; vs 30 °C, P=0.001) at 40 °C were higher than those at 20 and 30 °C. Arterial O2 partial pressure, O2 saturation, and pH at 40 °C were lower than those at 20 and 30 °C. Arterial CO2 partial pressure at 40 °C was higher than that at 20 and 30 °C. No differences were observed in arterial-mixed venous O2 concentration difference (P=0.391) and plasma lactate concentration (P=0.134) at different ambient temperatures. These results indicate that exercise at 40 °C causes excessive high body temperature, decreased running economy, and increased cardiac output compared to exercise at 20 and 30 °C. We strongly suggest that trainers and veterinarians should anticipate the occurrence of increased thermal stresses when ambient temperature is extremely high even in dry conditions and prepare to mitigate the risk of EHI from the perspective of equine welfare.
Collapse
Affiliation(s)
- Y. Ebisuda
- Sports Science Division, Equine Research Institute, Japan Racing Association, Shiba1400-4, Shimotsuke, Tochigi 329-0412, Japan
| | - K. Mukai
- Sports Science Division, Equine Research Institute, Japan Racing Association, Shiba1400-4, Shimotsuke, Tochigi 329-0412, Japan
| | - Y. Takahashi
- Sports Science Division, Equine Research Institute, Japan Racing Association, Shiba1400-4, Shimotsuke, Tochigi 329-0412, Japan
| | - H. Ohmura
- Sports Science Division, Equine Research Institute, Japan Racing Association, Shiba1400-4, Shimotsuke, Tochigi 329-0412, Japan
| |
Collapse
|
8
|
Trigg LE, Lyons S, Mullan S. Risk factors for, and prediction of, exertional heat illness in Thoroughbred racehorses at British racecourses. Sci Rep 2023; 13:3063. [PMID: 36918525 PMCID: PMC10015008 DOI: 10.1038/s41598-023-27892-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 01/10/2023] [Indexed: 03/16/2023] Open
Abstract
The development of exertional heat illness (EHI) is a health, welfare and performance concern for racehorses. However, there has been limited multivariable assessment of the possible risk factors for EHI in racehorses, despite such information being vital for regulators to effectively manage the condition. Consequently, this study aimed to identify the risk factors associated with the occurrence of EHI in Thoroughbred racehorses and assess the ability of the risk factor model to predict the occurrence of EHI in racehorses to assist in early identification. Runners at British racecourses recorded in the British Horseracing Authority database between 1st July 2010 and 30th April 2018 were used to model the probability that a horse would present with EHI as a function of a suite of environmental, horse level and race level factors. EHI was reported in 0.1% of runners. Race distance, wet bulb globe temperature, preceding 5-day temperature average, occurrence of a previous EHI incident, going, year and race off time were identified as risk factors for EHI. The model performed better than chance in classifying incidents with a mean area under the receiver operating characteristic curve score of 0.884 (SD = 0.02) but had a large number of false positives. The results provide vital evidence for industry on the need to provide appropriate cool down facilities, identify horses that have repeated EHI incidents for early intervention, and collect new data streams such as on course wet bulb globe temperature measurements. The results are especially relevant as the sport is operating in a changing climate and must mitigate against more extreme and longer spells of hot weather.
Collapse
Affiliation(s)
- Leah E Trigg
- Bristol Veterinary School, University of Bristol, Langford House, Langford, Bristol, BS40 5DU, UK.
| | - Sally Lyons
- British Horseracing Authority, 75 High Holborn, London, WC1V 6LS, UK
| | - Siobhan Mullan
- School of Veterinary Medicine, University College Dublin, Belfield, Dublin 4, Ireland
| |
Collapse
|
9
|
An Overview of Exertional Heat Illness in Thoroughbred Racehorses: Pathophysiology, Diagnosis, and Treatment Rationale. Animals (Basel) 2023; 13:ani13040610. [PMID: 36830397 PMCID: PMC9951674 DOI: 10.3390/ani13040610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 01/29/2023] [Accepted: 01/30/2023] [Indexed: 02/12/2023] Open
Abstract
Exertional heat illness (EHI) is a complex medical disease. The thoroughbred (TB) racehorse is at considerable risk because of the intensity of its exercise activity and its high rate of metabolic heat production. The pathophysiology of EHI can combine aspects of both the heat toxicity pathway and the heat sepsis or endotoxemic pathway. Treatment regimes depend upon the detection of earliest clinical signs, rapid assessment, aggressive cooling and judicious use of ancillary medications. Ice-cold water provides the most rapid cooling, consistent with the need to lower core body temperature before tissue damage occurs. Research into EHI/HS by inducing the condition experimentally is ethically unjustifiable. Consequently, leading researchers in the human field have conceded that "most of our knowledge has been gained from anecdotal incidents, gathered from military personnel and athletes who have collapsed during or following physical activity, and that retrospective and case studies have provided important evidence regarding recognition and treatment of EHI". The authors' review into EHI shares that perspective, and the recommendations made herein are based on observations of heat-affected racehorses at the racetrack and their response, or lack of response, to treatment. From 2014 to 2018, 73 race meetings were attended, and of the 4809 individual starters, signs of EHI were recorded in 457. That observational study formed the basis for a series of articles which have been published under the title, 'EHI in Thoroughbred racehorses in eastern Australia', and forms the background for this review.
Collapse
|
10
|
Cox EG, Bell R, Greer RM, Jeffcott LB. A survey on the use of rugs in Australian horses. Aust Vet J 2023; 101:9-26. [PMID: 36437593 PMCID: PMC10098481 DOI: 10.1111/avj.13219] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2022] [Revised: 11/02/2022] [Accepted: 11/04/2022] [Indexed: 11/29/2022]
Abstract
The practice of horse rugging has important implications for horse welfare and performance, but in Australia, rugging practices have not been properly documented. The objective of this study was to obtain an understanding of Australian horse rugging practices. An online survey reviewed the management of 2659 Australian horses over 12 months. Of the reported horses a total of 84.8% were rugged, although most owners (69.5%) indicated that they were unsure whether horses needed to be rugged at all. Rugging was felt by 59.8% of owners to be a requirement for horses in competition. Riding and competition were significantly associated with the use of rugs. Nearly all respondents (89.0%) felt that 'over-rugging' was a concern. However, 4.8% of owners would use up to 4 rugs at any one time on their horse and 21.4% of horses were still rugged in temperatures above 20°C in Australia. Many Australian horse owners (42.8%) also believe that horses feel cold if they are not rugged. Anthropomorphism when it comes to rugging horses cannot be justified as the horse has a much wider thermoneutral zone (TNZ) than humans. Australian climate, owner opinions, equestrian discipline and whether a horse is used for riding influence Australian horse rugging practices. However, current practices are based on limited available research and are not necessarily to the benefit of the horse. The major limitation was that the survey likely attracted respondents who are interested in the topic creating a self-selection bias.
Collapse
Affiliation(s)
- E G Cox
- The University of Sydney, Faculty of Science, Sydney School of Veterinary Science, The University Veterinary Teaching Hospital Camden, Sydney, Australia
| | - Rjw Bell
- The University of Sydney, Faculty of Science, Sydney School of Veterinary Science, The University Veterinary Teaching Hospital Camden, Sydney, Australia
| | - R M Greer
- Torus Research, Brisbane, Australia.,Faculty of Medicine, The University of Queensland, Mater Research Institute-UQ, South Brisbane, Australia
| | - L B Jeffcott
- The University of Sydney, Faculty of Science, Sydney School of Veterinary Science, The University Veterinary Teaching Hospital Camden, Sydney, Australia
| |
Collapse
|
11
|
Brownlow MA, Mizzi JX. Pathophysiology of exertional heat illness in the Thoroughbred racehorse: Broadening perspective to include an exercise‐induced gastrointestinal syndrome in which endotoxaemia and systemic inflammation may contribute to the condition. EQUINE VET EDUC 2022. [DOI: 10.1111/eve.13750] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Affiliation(s)
| | - James Xavier Mizzi
- Department of Regulation, Welfare and Biosecurity Policy The Hong Kong Jockey Club, Sha Tin Racecourse Sha Tin Hong Kong
| |
Collapse
|
12
|
Santos MM, Benvenuto GV, Ramos GV, Titotto AC, Adão MDS, de Lacerda LDCC, Lisbôa JAN, Lacerda-Neto JCD. Effect of Lactate Minimum Speed-Guided Conditioning on Selected Blood Parameters of Horses. J Equine Vet Sci 2022; 119:104133. [PMID: 36184020 DOI: 10.1016/j.jevs.2022.104133] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Revised: 09/17/2022] [Accepted: 09/26/2022] [Indexed: 12/14/2022]
Abstract
During exercise, equines can suffer severe water and electrolyte imbalances depending on the intensity and duration. In this sense, conditioning aims to promote adaptations to the organism in order to maintain cardiovascular and thermoregulatory stability during exertion. This study aimed to evaluate the effect of conditioning guided by lactate minimum speed (LMS) test on the blood osmolality of horses. We hypothesized that after conditioning the blood osmolality would vary less during exercise and that LMS could be used in equine conditioning program. Ten Arabian horses were evaluated before (ET 1) and after (ET 2) 6 weeks of conditioning. The conditioning intensity was established from the LMS during ET 1. The blood was obtained at rest and during the ETs. An increase in LMS and a decrease in lactate were seen in individual horses; however, these differences were not significant at a group level. No change in blood osmolality was observed when comparing the ETs. The plasma volume remained unchanged in ET 2. The conditioning guided by LMS improved the animals' fitness, which was evidenced by the lower lactate production in ET 2. The fact that the osmolality kept unchanged proves the effectiveness of the osmotic blood balance during exercise, as its control involves the interaction of different systems. Body adaptations occurred with conditioning, providing greater homeostasis control since the plasma volume remained stable in ET 2. It was concluded that the LMS test can be used to define an effective equine conditioning program even though some adjustments are still necessary.
Collapse
Affiliation(s)
- Maíra Moreira Santos
- Department of Clinic and Veterinary Surgery, Faculty of Agricultural and Veterinary Sciences, UNESP, São Paulo State University, Jaboticabal, São Paulo, Brazil
| | - Guilherme Vechiato Benvenuto
- Department of Clinic and Veterinary Surgery, Faculty of Agricultural and Veterinary Sciences, UNESP, São Paulo State University, Jaboticabal, São Paulo, Brazil
| | - Gabriel Vieira Ramos
- Department of Clinic and Veterinary Surgery, Faculty of Agricultural and Veterinary Sciences, UNESP, São Paulo State University, Jaboticabal, São Paulo, Brazil
| | - Angélica Cristina Titotto
- Department of Clinic and Veterinary Surgery, Faculty of Agricultural and Veterinary Sciences, UNESP, São Paulo State University, Jaboticabal, São Paulo, Brazil
| | - Milena Dos Santos Adão
- Department of Clinic and Veterinary Surgery, Faculty of Agricultural and Veterinary Sciences, UNESP, São Paulo State University, Jaboticabal, São Paulo, Brazil
| | - Luciana de Cenço Corrêa de Lacerda
- Department of Clinic and Veterinary Surgery, Faculty of Agricultural and Veterinary Sciences, UNESP, São Paulo State University, Jaboticabal, São Paulo, Brazil
| | | | - José Corrêa de Lacerda-Neto
- Department of Clinic and Veterinary Surgery, Faculty of Agricultural and Veterinary Sciences, UNESP, São Paulo State University, Jaboticabal, São Paulo, Brazil.
| |
Collapse
|
13
|
The Effects of an External Equine Nasal Strip on Thermoregulation During Exercise. J Equine Vet Sci 2022; 119:104141. [PMID: 36265545 DOI: 10.1016/j.jevs.2022.104141] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2022] [Revised: 10/12/2022] [Accepted: 10/14/2022] [Indexed: 11/06/2022]
Abstract
The purpose of this study was to examine the effects of an external nasal strip on thermoregulation during submaximal exercise in Standardbred horses. While several studies have been conducted to determine the effects of the external nasal strip on airway resistance, exercise induced pulmonary hemorrhage, gas exchange, and time to fatigue in maximally exercising horses, the effects of the nasal strip on equine thermoregulation have not yet been examined. It was hypothesized that the application of an external nasal strip would alter central venous temperature (Tcore), skin temperature (Tskin), and exercise time to reach a central venous temperature of 40 °C. Eight mature Standardbred horses each performed two submaximal exercise trials, one with a nasal strip (NS), and one without (control), on a high-speed equine treadmill with exercise concluding upon Tcore reaching 40 °C. There were no significant differences in Tcore or Tskin between the NS and control groups during pre-exercise, exercise or recovery (P > .05), nor were there differences (P > .05) in exercise time to reach a Tcore of 40 °C (NS: 11.8 ± 1.5 minutes; Control: 11.5 ± 1.1 min). We conclude that the application of an external nasal strip does not affect the equine thermoregulatory response during submaximal exercise.
Collapse
|
14
|
Hora M, Pontzer H, Struška M, Entin P, Sládek V. Comparing walking and running in persistence hunting. J Hum Evol 2022; 172:103247. [PMID: 36152433 DOI: 10.1016/j.jhevol.2022.103247] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/28/2022] [Revised: 07/27/2022] [Accepted: 07/28/2022] [Indexed: 10/31/2022]
Abstract
It has been proposed that humans' exceptional locomotor endurance evolved partly with foraging in hot open habitats and subsequently about 2 million years ago with persistence hunting, for which endurance running was instrumental. However, persistence hunting by walking, if successful, could select for locomotor endurance even before the emergence of any running-related traits in human evolution. Using a heat exchange model validated here in 73 humans and 55 ungulates, we simulated persistence hunts for prey of three sizes (100, 250, and 400 kg) and three sweating capacities (nonsweating, low, high) at 6237 combinations of hunter's velocity (1-5 m s-1, intermittent), air temperature (25-45 °C), relative humidity (30-90%), and start time (8:00-16:00). Our simulations predicted that walking would be successful in persistence hunting of low- and nonsweating prey, especially under hot and humid conditions. However, simulated persistence hunts by walking yielded a 30-74% lower success rate than hunts by running or intermittent running. In addition, despite requiring 10-30% less energy, successful simulated persistence hunts by walking were twice as long and resulted in greater exhaustion of the hunter than hunts by running and intermittent running. These shortcomings of pursuit by walking compared to running identified in our simulations could explain why there is only a single direct description of persistence hunting by walking among modern hunter-gatherers. Nevertheless, walking down prey could be a viable option for hominins who did not possess the endurance-running phenotype of the proposed first persistence hunter, Homo erectus. Our simulation results suggest that persistence hunting could select for both long-distance walking and endurance running and contribute to the evolution of locomotor endurance seen in modern humans.
Collapse
Affiliation(s)
- Martin Hora
- Department of Anthropology and Human Genetics, Charles University, Viničná 7, Prague, 12800, Czech Republic; Department of Evolutionary Anthropology, Duke University, 130 Science Drive, Durham, NC, 27708, USA.
| | - Herman Pontzer
- Department of Evolutionary Anthropology, Duke University, 130 Science Drive, Durham, NC, 27708, USA; Global Health Institute, Duke University, 310 Trent Drive, Durham, NC, 27710, USA
| | - Michal Struška
- Department of Anthropology and Human Genetics, Charles University, Viničná 7, Prague, 12800, Czech Republic
| | - Pauline Entin
- College of Arts & Sciences, University of Massachusetts Dartmouth, 285 Old Westport Road, Dartmouth, MA, 02747, USA
| | - Vladimír Sládek
- Department of Anthropology and Human Genetics, Charles University, Viničná 7, Prague, 12800, Czech Republic
| |
Collapse
|
15
|
Sponseller BT, Wong DM, Ruby R, Ware WA, Wilson S, Haynes JS. Systemic calcinosis in a Quarter Horse gelding homozygous for a myosin heavy chain 1 mutation. J Vet Intern Med 2022; 36:1543-1549. [PMID: 35801821 PMCID: PMC9308413 DOI: 10.1111/jvim.16481] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/06/2022] [Accepted: 06/16/2022] [Indexed: 12/02/2022] Open
Abstract
Case Description A 9‐year‐old Quarter Horse gelding was presented for lethargy, decreased appetite, polyuria and polydipsia (PU/PD), and severe muscle wasting suggestive of immune‐mediated myositis. Clinical Findings The horse displayed lethargy, fever, tachyarrhythmia, inappetence, PU/PD, and severe epaxial and gluteal muscle wasting. Clinicopathologic findings were consistent with previously reported cases of systemic calcinosis in horses, including increased muscle enzyme activity, hyperphosphatemia, increased calcium‐phosphorus product, hypoproteinemia, and an inflammatory leukogram. A diagnosis of systemic calcinosis was established by histopathologic evaluation of biopsy specimens from skeletal muscle, lung, and kidney. Treatment and Outcome Symptomatic treatment was complemented by IV treatment with sodium thiosulfate to reverse calcium‐phosphate precipitation in soft tissue and PO aluminum hydroxide to decrease intestinal phosphorus absorption and serum phosphorus concentration. Clinical Relevance This is the first report in the veterinary literature of an antemortem diagnosis of systemic calcinosis in the horse that was successfully treated and had favorable long‐term outcome.
Collapse
Affiliation(s)
- Beatrice T Sponseller
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
| | - David M Wong
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
| | - Rebecca Ruby
- Veterinary Diagnostic Laboratory, College of Agriculture, Food and Environment, University of Kentucky, Lexington, Kentucky, USA
| | - Wendy A Ware
- Department of Veterinary Clinical Sciences, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
| | - Scott Wilson
- Mid-Atlantic Equine Dentistry, Myrtle Beach, South Carolina, USA
| | - Joseph S Haynes
- Department of Veterinary Pathology, College of Veterinary Medicine, Iowa State University, Ames, Iowa, USA
| |
Collapse
|
16
|
Verdegaal ELJMM, Howarth GS, McWhorter TJ, Delesalle CJG. Is Continuous Monitoring of Skin Surface Temperature a Reliable Proxy to Assess the Thermoregulatory Response in Endurance Horses During Field Exercise? Front Vet Sci 2022; 9:894146. [PMID: 35711810 PMCID: PMC9196037 DOI: 10.3389/fvets.2022.894146] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 04/25/2022] [Indexed: 11/13/2022] Open
Abstract
Hyperthermia is a performance and welfare issue for exercising horses. The thermoregulatory stressors associated with exercise have typically been estimated by responses in the laboratory. However, monitoring surface skin temperature (Tsk) coincident with core temperature (Tc) has not previously been investigated in horses exercising in the field. We investigated the suitability of monitoring surface Tsk as a metric of the thermoregulatory response, and simultaneously investigated its relationship with Tc using gastrointestinal (GI) temperature. We evaluated Tsk in 13 endurance horses competing during four endurance rides over 40 km (n = 1) or a total of 80 km (n = 12) distance. Following each 40-km loop, the horses were rested for 60 min. Tsk and Tc were continuously recorded every 15 s by an infrared thermistor sensor located in a modified belt and by telemetric GI pill, respectively, and expressed as mean ± SD. The net area under the curve (AUC) was calculated to estimate the thermoregulatory response to the thermal load of Tsk over time (°C × minutes) using the trapezoidal method. The relationship between Tsk and Tc was assessed using scatterplots, paired t-test or generalized linear model ANOVA (delta Tsk) (n = 8). Ambient temperature ranged from 6.7°C to 18.4°C. No relationship was found between Tsk and Tc profiles during exercise and recovery periods, and no significant difference between delta Tsk results was detected when comparing exercise and rest. However, time to maximum Tsk (67 min) was significantly reduced compared to Tc (139 min) (p = 0.0004) with a significantly lesser maximum Tsk (30.3°C) than Tc (39°C) (p = 0.0002) during exercise. Net AUC Tsk was 1,164 ± 1,448 and −305 ± 388°C × minutes during periods of exercise and recovery, respectively. We conclude that Tsk monitoring does not provide a reliable proxy for the thermoregulatory response and horse welfare, most probably because many factors can modulate Tsk without directly affecting Tc. Those factors, such as weather conditions, applicable to all field studies can influence the results of Tsk in endurance horses. The study also reveals important inter-individual differences in Tsk and Tc time profiles, emphasizing the importance of an individualized model of temperature monitoring.
Collapse
Affiliation(s)
- Elisabeth-Lidwien J. M. M. Verdegaal
- Equine Health and Performance Centre, University of Adelaide, Adelaide, SA, Australia
- Department of Translational Physiology, Infectiology and Public Health, Research Group of Comparative Physiology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
- *Correspondence: Elisabeth-Lidwien J. M. M. Verdegaal
| | - Gordon S. Howarth
- Equine Health and Performance Centre, University of Adelaide, Adelaide, SA, Australia
- Gastroenterology Department, Women's and Children's Hospital, Adelaide, SA, Australia
| | - Todd J. McWhorter
- Equine Health and Performance Centre, University of Adelaide, Adelaide, SA, Australia
| | - Catherine J. G. Delesalle
- Department of Translational Physiology, Infectiology and Public Health, Research Group of Comparative Physiology, Faculty of Veterinary Medicine, Ghent University, Merelbeke, Belgium
| |
Collapse
|
17
|
Kang H, Zsoldos RR, Skinner JE, Gaughan JB, Mellor VA, Sole-Guitart A. The Use of Percutaneous Thermal Sensing Microchips to Measure Body Temperature in Horses during and after Exercise Using Three Different Cool-Down Methods. Animals (Basel) 2022; 12:ani12101267. [PMID: 35625113 PMCID: PMC9137820 DOI: 10.3390/ani12101267] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2022] [Revised: 05/05/2022] [Accepted: 05/13/2022] [Indexed: 01/27/2023] Open
Abstract
The frequent monitoring of a horse’s body temperature post strenuous exercise is critical to prevent or alleviate exertional heat illness (EHI) from occurring. Percutaneous thermal sensing microchip (PTSM) technology has the potential to be used as a means of monitoring a horse’s body temperature during and post-exercise. However, the accuracy of the temperature readings obtained, and their relationship to core body temperature are dependent on where they are implanted. This study aimed to document the relationship between core body temperature, and temperature readings obtained using PTSM implanted in different muscles, during exercise and post application of different cool-down methods. PTSMs were implanted into the right pectoral, right gluteal, right splenius muscles, and nuchal ligament. The temperatures were monitored during treadmill exercise, and post application of three different cool-down methods: no water application (Wno), water application only (Wonly), and water application following scraping (Wscraping). Central venous temperature (TCV) and PTSM temperatures from each region were obtained to investigate the optimal body site for microchip implantation. In this study, PTSM technology provided a practical, safe, and quick means of measuring body temperature in horses. However, its temperature readings varied depending on the implantation site. All muscle temperature readings exhibited strong relationships with TCV (r = 0.85~0.92, p < 0.05) after treadmill exercise without human intervention (water application), while the nuchal ligament temperature showed poor relationship with TCV. The relationships between TCV and PTSM temperatures became weaker with water application. Overall, however the pectoral muscle temperature measured by PTSM technology had the most constant relationships with TCV and showed the best potential to act as an alternate means of monitoring body temperature in horses for 50 min post-exercise, when there was no human intervention with cold water application.
Collapse
Affiliation(s)
- Hyungsuk Kang
- School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD 4343, Australia; (H.K.); (R.R.Z.); (J.E.S.); (J.B.G.); (V.A.M.)
| | - Rebeka R. Zsoldos
- School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD 4343, Australia; (H.K.); (R.R.Z.); (J.E.S.); (J.B.G.); (V.A.M.)
| | - Jazmine E. Skinner
- School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD 4343, Australia; (H.K.); (R.R.Z.); (J.E.S.); (J.B.G.); (V.A.M.)
- School of Agriculture and Environment, University of Southern Queensland, Toowoomba, QLD 4350, Australia
| | - John B. Gaughan
- School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD 4343, Australia; (H.K.); (R.R.Z.); (J.E.S.); (J.B.G.); (V.A.M.)
| | - Vincent A. Mellor
- School of Agriculture and Food Sciences, The University of Queensland, Gatton, QLD 4343, Australia; (H.K.); (R.R.Z.); (J.E.S.); (J.B.G.); (V.A.M.)
| | - Albert Sole-Guitart
- School of Veterinary Science, The University of Queensland, Gatton, QLD 4343, Australia
- Correspondence:
| |
Collapse
|
18
|
Brownlow M, Mizzi JX. Epidemiology of exertional heat illness in Thoroughbred racehorses in temperate eastern Australia: The role of extrinsic (environmental) factors in disease causation. EQUINE VET EDUC 2022. [DOI: 10.1111/eve.13627] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- M. Brownlow
- Racing Australia Sydney New South Wales Australia
| | - J. X. Mizzi
- Department of Regulation, Welfare and Biosecurity Policy The Hong Kong Jockey Club, Sha Tin Racecourse Hong Kong Sha Tin China
| |
Collapse
|
19
|
Verdegaal ELJMM, Howarth GS, McWhorter TJ, Boshuizen B, Franklin SH, Vidal Moreno de Vega C, Jonas SE, Folwell LE, Delesalle CJG. Continuous Monitoring of the Thermoregulatory Response in Endurance Horses and Trotter Horses During Field Exercise: Baselining for Future Hot Weather Studies. Front Physiol 2021; 12:708737. [PMID: 34512382 PMCID: PMC8427666 DOI: 10.3389/fphys.2021.708737] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Accepted: 07/29/2021] [Indexed: 11/15/2022] Open
Abstract
Establishing proper policies regarding the recognition and prevention of equine heat stress becomes increasingly important, especially in the face of global warming. To assist this, a detailed view of the variability of equine thermoregulation during field exercise and recovery is essential. 13 endurance horses and 12 trotter horses were equipped with continuous monitoring devices [gastrointestinal (GI) pill, heartrate (HR) monitor, and global positioning system] and monitored under cool weather conditions during four endurance rides over a total of 80 km (40 km loops) and intense trotter track-based exercise over 1,540 m. Recordings included GI temperature (T c ), speed, HR and pre- and post-exercise blood values. A temperature time profile curve of T c was constructed, and a net area under the curve was calculated using the trapezoidal method. Metabolic heat production and oxygen cost of transport were also calculated in endurance horses. Maximum T c was compared using an independent samples t-test. Endurance horses (mean speed 14.1 ± 1.7 km h-1) reached mean maximum T c (39.0 ± 0.4°C; 2 × 40 km in 8 horses) during exercise at 75% of completion of T c exercise and T c returned to baseline within 60 min into recovery. However, the mean T c was still 38.8 ± 0.4°C at a HR of 60 bpm which currently governs "fit to continue" competition decisions. Trotters (40.0 ± 2.9 km h-1) reached a comparable mean max T c (38.8 ± 0.5°C; 12 horses) always during recovery. In 30% of trotters, T c was still >39°C at the end of recovery (40 ± 32 min). The study shows that horses are individuals and thermoregulation monitoring should reflect this, no matter what type of exercise is performed. Caution is advised when using HR cut-off values to monitor thermal welfare in horses since we have demonstrated how T c can peak quite some time after finishing exercise. These findings have implications for training and management of performance horses to safeguard equine welfare and to maximize performance.
Collapse
Affiliation(s)
- Elisabeth-Lidwien J. M. M. Verdegaal
- Equine Health and Performance Centre, University of Adelaide, Adelaide, SA, Australia
- School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Adelaide, SA, Australia
- Research Group of Comparative Physiology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Gordon S. Howarth
- School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Adelaide, SA, Australia
| | - Todd J. McWhorter
- School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Adelaide, SA, Australia
| | - Berit Boshuizen
- Research Group of Comparative Physiology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Samantha H. Franklin
- Equine Health and Performance Centre, University of Adelaide, Adelaide, SA, Australia
- School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Adelaide, SA, Australia
| | - Carmen Vidal Moreno de Vega
- Research Group of Comparative Physiology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| | - Stacey E. Jonas
- School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Adelaide, SA, Australia
| | - Louise E. Folwell
- School of Animal and Veterinary Sciences, Roseworthy Campus, University of Adelaide, Adelaide, SA, Australia
| | - Catherine J. G. Delesalle
- Research Group of Comparative Physiology, Department of Virology, Parasitology and Immunology, Faculty of Veterinary Medicine, Ghent University, Ghent, Belgium
| |
Collapse
|
20
|
Brownlow MA, Brotherhood JR. An investigation into environmental variables influencing post-race exertional heat illness in thoroughbred racehorses in temperate eastern Australia. Aust Vet J 2021; 99:473-481. [PMID: 34355381 DOI: 10.1111/avj.13108] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2021] [Revised: 06/29/2021] [Accepted: 07/01/2021] [Indexed: 11/30/2022]
Abstract
Exertional heat illness (EHI) is a syndrome that occurs when metabolic heat production from muscular contraction exceeds the rate at which it can be dissipated. Core body temperature rises to critical levels, causing hyperthermia and central nervous system dysfunction. Best practice for the prevention of EHI centres around early detection, rapid response and aggressive cooling. Advance planning enables risk mitigation measures. The more that is known about EHI in horses, the better prepared those in the positions of responsibility can be to anticipate events in which the risk of EHI may be elevated. This prospective, observational study investigated environmental risk factors associated with the occurrence of EHI. From 2014 to 2018, the number of horses exhibiting the symptoms of post-race EHI was recorded at 73 convenience sampled race meetings. Of the 4809 starters, the signs of EHI were recorded for 457. Thermal environmental data were measured and included ambient temperature, radiant heat, vapor pressure (humidity) and wind speed (WS). Mixed linear regression models were computed to assess the associations between the occurrence and incidence of post-race EHI and the four thermal environmental variables. The analysis showed that vapor pressure and WS had the largest effects on the occurrence of post-race EHI. The major limitations were that the race meetings selected were convenience sampled according to attendance by the first author and individual horse data were not available. EHI is influenced by a complex interaction of independently acting environmental variables, but warm, windless, humid days are most likely to result in the cases of EHI.
Collapse
Affiliation(s)
- M A Brownlow
- Racing Australia, Druitt Street, Sydney, New South Wales, 2000, Australia
| | - J R Brotherhood
- Discipline of Exercise and Sports Science, School of Health Sciences, Faculty of Medicine and Health, University of Sydney, Australia
| |
Collapse
|
21
|
Maśko M, Witkowska-Piłaszewicz O, Jasiński T, Domino M. Thermal features, ambient temperature and hair coat lengths: Limitations of infrared imaging in pregnant primitive breed mares within a year. Reprod Domest Anim 2021; 56:1315-1328. [PMID: 34310786 PMCID: PMC9292174 DOI: 10.1111/rda.13994] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2021] [Accepted: 07/24/2021] [Indexed: 11/28/2022]
Abstract
Infrared thermography is a non‐invasive technique which allows to distinguish between pregnant and non‐pregnant animals. Detecting accurate body surface temperatures can be challenging due to external factors altering thermograph measurements. This study aimed to determine the associations between the ambient temperature, the hair coat features and the temperatures of mares' abdomens. It compared pregnant and non‐pregnant mares throughout 11 months. The research was carried out on 40 Konik Polski mares, which were divided into pregnant and non‐pregnant groups. The temperature (Tmax, maximal; Taver, average; Tmin, minimal) of the mares' abdomen was evaluated in two regions of interest: the whole area of the lateral surface of the mares' abdomen (Px1) and the flank area of the lateral surface of mares' abdomen (Px2). During the increasing period, the slopes in the linear regression equation did not differ significantly for ambient (Tamb) and surface temperatures in both groups. In the decreasing period, the slopes did not differ significantly for Tamb and Tmax in the non‐pregnant group. They also did not differ for Tamb and Taver in Px1 and Tamb and Tmin in Px1 in both pregnant and non‐pregnant groups respectively. Other slopes varied significantly (p < .001). There was no evidence of parallel changes in hair coat features and measured temperatures. The flank area appears more suitable for thermal imaging in pregnant mares due to the seasonal fluctuations in hair coat lengths.
Collapse
Affiliation(s)
- Małgorzata Maśko
- Department of Animal Breeding, Institute of Animal Science, Warsaw University of Life Sciences (WULS - SGGW), Warsaw, Poland
| | - Olga Witkowska-Piłaszewicz
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences (WULS - SGGW), Warsaw, Poland
| | - Tomasz Jasiński
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences (WULS - SGGW), Warsaw, Poland
| | - Małgorzata Domino
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences (WULS - SGGW), Warsaw, Poland
| |
Collapse
|
22
|
Maśko M, Zdrojkowski Ł, Wierzbicka M, Domino M. Association between the Area of the Highest Flank Temperature and Concentrations of Reproductive Hormones during Pregnancy in Polish Konik Horses-A Preliminary Study. Animals (Basel) 2021; 11:1517. [PMID: 34071111 PMCID: PMC8224734 DOI: 10.3390/ani11061517] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/22/2021] [Revised: 05/18/2021] [Accepted: 05/20/2021] [Indexed: 02/01/2023] Open
Abstract
Determination of the pregnancy status is one of the most important factors for effective pregnancy management. Knowledge of the stage of pregnancy is important to interpret many of the reproductive hormones' concentrations, including progesterone (P4), estrone sulfate (E1S), 17-ß estradiol (E2), and relaxin (REL). However, it is limited in wildlife or captive equids that cannot be handled. Reproductive hormones affect regional blood flow, the proliferation of tissues, and local metabolism intensity. Therefore, this preliminary study aimed to assess changes in thermal features of the abdomen lateral surface and concentrations of reproductive hormones in Polish native pregnant mares. The study was carried out on 14 non-pregnant and 26 pregnant Polish Konik mares during eleven months of pregnancy. Infrared thermography was conducted to image the lateral surface of mares' abdomen (Px1) and flank area (Px2); P4, E1S, E2, and REL concentrations in serum were also determined. The evidence of the association between the area with the highest temperatures (Area of Tmax) and serum concentrations of P4 (the slope = 1.373; p = 0.9245) and REL (the slope = 1.342; p = 0.4324) were noted dependent across months of pregnancy. Measures of superficial body temperatures were found to change monthly, similarly to ambient temperatures, with no evidence of coincidence with changes in reproductive hormone concentrations. Individual thermal characteristics of the lateral surface of the abdomen differed between pregnant and non-pregnant mares in other periods. Differences in maximal and average temperature and Area of Tmax were observed from the sixth month of pregnancy, and those in minimal temperature were observed from the eighth month.
Collapse
Affiliation(s)
- Małgorzata Maśko
- Department of Animal Breeding, Institute of Animal Science, Warsaw University of Life Sciences, 02-787 Warsaw, Poland;
| | - Łukasz Zdrojkowski
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (Ł.Z.); (M.W.)
| | - Małgorzata Wierzbicka
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (Ł.Z.); (M.W.)
| | - Małgorzata Domino
- Department of Large Animal Diseases and Clinic, Institute of Veterinary Medicine, Warsaw University of Life Sciences, 02-787 Warsaw, Poland; (Ł.Z.); (M.W.)
| |
Collapse
|
23
|
McGill S, Coleman B, Hayes M. Air Speed to Increase Rate of Cool Out for Horses After Intense Exercise. J Equine Vet Sci 2021; 102:103641. [PMID: 34119195 DOI: 10.1016/j.jevs.2021.103641] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/26/2021] [Revised: 03/29/2021] [Accepted: 04/15/2021] [Indexed: 11/30/2022]
Abstract
Cooling out horses is a common practice after intense exercise. Typical cooling procedures include both walking and drenching (often with scraping). The cool out is performed to ensure the horses physiologic responses returned to a baseline range as quickly as possible. The use of water in cool out provides the greatest potential for removing heat from the animals. However, adding air velocities that can increase evaporation rates from the horses can potentially increase the rate of cool out; thereby reducing the time until the horses' physiologic measurements return to baseline. This study measured the rate of cool out for 7 Thoroughbreds, which were run on the track for 1 or 1.5 miles. Animals were provided a combination of walking and drenching in addition to 3 fan treatments no fan, fan directed at lateral side, and fan directed at posterior. Physiologic responses were analyzed using the Multivariate analysis of variance (MANOVA) procedure and while no significant differences were found in the rate of cool out, trends indicated both rectal temperature (P = .10) and heart rate (P = .11) returned to baseline more quickly with the addition of a fan.
Collapse
Affiliation(s)
- Staci McGill
- Department of Biosystems and Agricultural Engineering, University of Kentucky, Lexington, KY
| | - Bob Coleman
- Department of Animal and Food Sciences, University of Kentucky, Lexington, KY
| | - Morgan Hayes
- Department of Biosystems and Agricultural Engineering, University of Kentucky, Lexington, KY.
| |
Collapse
|
24
|
Brownlow MA, Mizzi JX. Exertional heat illness in Thoroughbred racehorses – Pathophysiology, case definition and treatment rationale. EQUINE VET EDUC 2021. [DOI: 10.1111/eve.13459] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Affiliation(s)
| | - J. X. Mizzi
- 315 Singles Ridge Road Yellow Rock New South Wales Australia
| |
Collapse
|
25
|
Mishra AK, Pan W, Giannelis EP, Shepherd RF, Wallin TJ. Making bioinspired 3D-printed autonomic perspiring hydrogel actuators. Nat Protoc 2021; 16:2068-2087. [PMID: 33627845 DOI: 10.1038/s41596-020-00484-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 12/14/2020] [Indexed: 11/09/2022]
Abstract
To mitigate the adverse effects of elevated temperatures, conventional rigid devices use bulky radiators, heat sinks and fans to dissipate heat from sensitive components. Unfortunately, these thermoregulation strategies are incompatible with soft robots, a growing field of technology that, like biology, builds compliant and highly deformable bodies from soft materials to enable functional adaptability. Here, we design fluidic elastomer actuators that autonomically perspire at elevated temperatures. This strategy incurs operational penalties (i.e., decreased actuation efficiency and loss of hydraulic fluid) but provides for thermoregulation in soft systems. In this bioinspired approach, we 3D-print finger-like actuators from smart gels with embedded micropores that autonomically dilate and contract in response to temperature. During high-temperature operation, the internal hydraulic fluid flows through the dilated pores, absorbs heat and vaporizes. Upon cooling, the pores contract to restrict fluid loss and restore operation. To assess the thermoregulatory performance, this protocol uses non-invasive thermography to measure the local temperatures of the robot under varied conditions. A mathematical model based on Newton's law of cooling quantifies the cooling performance and enables comparison between competing designs. Fabrication of the sweating actuator usually takes 3-6 h, depending on size, and can provide >100 W/kg of additional cooling capacity.
Collapse
Affiliation(s)
- Anand Kumar Mishra
- Department of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA
| | - Wenyang Pan
- Facebook Reality Labs, Redmond, WA, USA.,Department of Materials Science and Engineering, Cornell University, Ithaca, NY, USA
| | - Emmanuel P Giannelis
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY, USA
| | - Robert F Shepherd
- Department of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY, USA
| | - Thomas J Wallin
- Facebook Reality Labs, Redmond, WA, USA. .,Department of Materials Science and Engineering, Cornell University, Ithaca, NY, USA.
| |
Collapse
|
26
|
Mishra AK, Wallin TJ, Pan W, Xu P, Wang K, Giannelis EP, Mazzolai B, Shepherd RF. Autonomic perspiration in 3D-printed hydrogel actuators. Sci Robot 2021; 5:5/38/eaaz3918. [PMID: 33022596 DOI: 10.1126/scirobotics.aaz3918] [Citation(s) in RCA: 75] [Impact Index Per Article: 25.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/05/2019] [Accepted: 12/17/2019] [Indexed: 12/13/2022]
Abstract
In both biological and engineered systems, functioning at peak power output for prolonged periods of time requires thermoregulation. Here, we report a soft hydrogel-based actuator that can maintain stable body temperatures via autonomic perspiration. Using multimaterial stereolithography, we three-dimensionally print finger-like fluidic elastomer actuators having a poly-N-isopropylacrylamide (PNIPAm) body capped with a microporous (~200 micrometers) polyacrylamide (PAAm) dorsal layer. The chemomechanical response of these hydrogel materials is such that, at low temperatures (<30°C), the pores are sufficiently closed to allow for pressurization and actuation, whereas at elevated temperatures (>30°C), the pores dilate to enable localized perspiration in the hydraulic actuator. Such sweating actuators exhibit a 600% enhancement in cooling rate (i.e., 39.1°C minute-1) over similar non-sweating devices. Combining multiple finger actuators into a single device yields soft robotic grippers capable of both mechanically and thermally manipulating various heated objects. The measured thermoregulatory performance of these sweating actuators (~107 watts kilogram-1) greatly exceeds the evaporative cooling capacity found in the best animal systems (~35 watts kilogram-1) at the cost of a temporary decrease in actuation efficiency.
Collapse
Affiliation(s)
- Anand K Mishra
- Department of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14850, USA
| | - Thomas J Wallin
- Facebook Reality Labs, Redmond, WA 98052, USA.,Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14850, USA
| | - Wenyang Pan
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14850, USA
| | - Patricia Xu
- Department of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14850, USA
| | - Kaiyang Wang
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14850, USA
| | - Emmanuel P Giannelis
- Department of Materials Science and Engineering, Cornell University, Ithaca, NY 14850, USA
| | - Barbara Mazzolai
- Center for Micro-Biorobotics, Istituto Italiano di Technologia, Pontedera, PI 56025 Pisa, Italy
| | - Robert F Shepherd
- Department of Mechanical and Aerospace Engineering, Cornell University, Ithaca, NY 14850, USA.
| |
Collapse
|
27
|
Lindinger MI, Waller AP. Tracing oral Na
+
and K
+
in sweat during exercise and recovery in horses. Exp Physiol 2021; 106:972-982. [DOI: 10.1113/ep089232] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2020] [Accepted: 02/02/2021] [Indexed: 11/08/2022]
Affiliation(s)
- Michael I. Lindinger
- Research and Development The Nutraceutical Alliance Inc. Burlington Ontario Canada
| | - Amanda P. Waller
- Center for Clinical & Translational Research Nationwide Children's Hospital Columbus OH USA
| |
Collapse
|
28
|
Brownlow MA, Mizzi JX. Thermoregulatory capacity of the Thoroughbred racehorse and its relationship to the pathogenesis of exertional heat illness. EQUINE VET EDUC 2020. [DOI: 10.1111/eve.13433] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
29
|
Klous L, Siegers E, van den Broek J, Folkerts M, Gerrett N, van Oldruitenborgh-Oosterbaan MS, Munsters C. Effects of Pre-Cooling on Thermophysiological Responses in Elite Eventing Horses. Animals (Basel) 2020; 10:ani10091664. [PMID: 32947831 PMCID: PMC7552184 DOI: 10.3390/ani10091664] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Revised: 08/28/2020] [Accepted: 09/07/2020] [Indexed: 01/21/2023] Open
Abstract
Simple Summary Horses have a high metabolic capacity for exercise, producing a great deal of heat, and have a small surface area for heat loss. Under limited circumstances, the regulation of heat loss (i.e., across the respiratory tract and by the evaporation of sweat) means heat build-up in the body is reduced. Thermoregulation can be assisted by cooling the horses down to safely perform exercise in thermally challenging environments. The present study showed that pre-cooling (i.e., cooling between the warm-up and exercise performance) slightly reduced the rise in rectal, shoulder and rump skin temperatures of ten international eventing horses during moderately intense canter training in moderate environmental conditions. During the canter training, heart rate, sweat rate and sweat composition were unaffected by pre-cooling. The pre-cooling strategy chosen here was cold-water rinsing for a short period of time (~8 min). Considering the limited time and space at equestrian events, such a pre-cooling strategy could easily be implemented. Reducing heat strain by pre-cooling may potentially improve equine welfare during events. Abstract In this study, we examined the effects of pre-cooling on thermophysiological responses in horses exercising in moderate environmental conditions (average wet bulb globe temperature: 18.5 ± 3.8 °C). Ten international eventing horses performed moderate intensity canter training on two separate days, and were either pre-cooled with cold-water rinsing (5–9 °C for 8 ± 3 min; cooling) or were not pre-cooled (control). We determined velocity (V), heart rate (HR), rectal temperature (Tre,), shoulder and rump skin temperature (Tshoulder and Trump), plasma lactate concentration (LA), gross sweat loss (GSL), and local sweat rate (LSR), as well as sweat sodium, chloride and potassium concentrations. The effect of pre-cooling on Tre was dependent on time; after 20 min of exercise the effect was the largest (estimate: 0.990, 95% likelihood confidence intervals (95% CI): 0.987, 0.993) compared to the control condition, resulting in a lower median Tre of 0.3 °C. Skin temperature was also affected by pre-cooling compared to the control condition (Tshoulder: −3.30 °C, 95% CI: −3.739, −2.867; Trump: −2.31 °C, 95% CI: −2.661, −1.967). V, HR, LA, GSL, LSR and sweat composition were not affected by pre-cooling. In conclusion, pre-cooling by cold-water rinsing could increase the margin for heat storage, allowing a longer exercise time before a critical Tre is reached and, therefore, could potentially improve equine welfare during competition.
Collapse
Affiliation(s)
- Lisa Klous
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Van der Boechorststraat 7-9, 1081 BT Amsterdam, The Netherlands; (L.K.); (M.F.); (N.G.)
| | - Esther Siegers
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 112, 3584 CM Utrecht, The Netherlands; (E.S.); (M.S.v.O.-O.)
| | - Jan van den Broek
- Department of Population Health Sciences, Utrecht University, Yalelaan 7, 3584 CL Utrecht, The Netherlands;
| | - Mireille Folkerts
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Van der Boechorststraat 7-9, 1081 BT Amsterdam, The Netherlands; (L.K.); (M.F.); (N.G.)
| | - Nicola Gerrett
- Department of Human Movement Sciences, Faculty of Behavioural and Movement Sciences, Vrije Universiteit Amsterdam, Amsterdam Movement Sciences, Van der Boechorststraat 7-9, 1081 BT Amsterdam, The Netherlands; (L.K.); (M.F.); (N.G.)
| | | | - Carolien Munsters
- Department of Clinical Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 112, 3584 CM Utrecht, The Netherlands; (E.S.); (M.S.v.O.-O.)
- Moxie Sport Analysis & Coaching, Looieind 1, 5469 Erp, The Netherlands
- Correspondence: ; Tel.: +31-6125-097-19
| |
Collapse
|
30
|
A Comparison of Five Cooling Methods in Hot and Humid Environments in Thoroughbred Horses. J Equine Vet Sci 2020; 91:103130. [DOI: 10.1016/j.jevs.2020.103130] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2020] [Revised: 05/13/2020] [Accepted: 05/14/2020] [Indexed: 01/16/2023]
|
31
|
Halsey LG, Bryce CM. Are humans evolved specialists for running in the heat? Man
vs
. horse races provide empirical insights. Exp Physiol 2020; 106:258-268. [DOI: 10.1113/ep088502] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2020] [Accepted: 06/23/2020] [Indexed: 11/08/2022]
Affiliation(s)
- Lewis G. Halsey
- Department of Life Sciences University of Roehampton London SW15 4JD UK
| | - Caleb M. Bryce
- Botswana Predator Conservation Trust Private Bag 13 Maun Botswana
| |
Collapse
|
32
|
Brownlow M, Smith T. The use of the hand‐held infrared thermometer as an early detection tool for exertional heat illness in Thoroughbred racehorses: A study at racetracks in eastern Australia. EQUINE VET EDUC 2020. [DOI: 10.1111/eve.13299] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Affiliation(s)
- M. Brownlow
- Racing Australia Sydney New South Wales Australia
| | - T. Smith
- Racing Australia Sydney New South Wales Australia
| |
Collapse
|
33
|
Takahashi Y, Takahashi T. Risk factors for exertional heat illness in Thoroughbred racehorses in flat races in Japan (2005-2016). Equine Vet J 2019; 52:364-368. [PMID: 31505059 DOI: 10.1111/evj.13179] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Accepted: 08/29/2019] [Indexed: 01/24/2023]
Abstract
BACKGROUND Exertional heat illness (EHI) is recognised in horses, but few reports have investigated its risk factors. OBJECTIVES To identify risk factors for EHI in racehorses participating in flat races in Japan. STUDY DESIGN Descriptive epidemiology and retrospective unmatched case-control study. METHODS Between 2005 and 2016, veterinary records of horses diagnosed with EHI after flat races were reviewed retrospectively and data of the months from April to September were used for a case-control study. For each case, three control horses were randomly selected from starts between April and September. Race records of horses and estimated wet-bulb globe temperature (WBGT) indexes at the local meteorological observatory closest to the racecourse were investigated. To identify risk factors for EHI, univariable and multivariable logistic regression analysis was used. RESULTS Of 194 cases during the study period, 188 cases occurred between April and September. The highest incidence risk was in July (1.1 cases per 1000 starts, 95% confidence interval 0.84-1.45). In the final multivariable model, WBGT index, sex, race distance, age and bodyweight were associated with EHI. When WBGT index exceeded 28°C, the risk of EHI was considerably higher than <20°C (OR 28.5, 14.2-62.4, P<0.001). Compared with uncastrated males, geldings (OR 4.9, 1.8-13.3, p = 0.002) and females (OR 2.4, 1.5-3.7, P<0.001) were at high risk of EHI (P<0.01). Furthermore, races of >1600 m (OR 1.8, 1.2-2.8, P = 0.002), 4-year-old (OR 3.5, 1.6-7.9, P = 0.002) and ≥5-year-old (OR 3.9, 1.8-9.2, P = 0.001) horses and horses with low bodyweight (OR per 20 kg, 0.8, 0.7-1.0, P = 0.02) were associated with increased risk of EHI. MAIN LIMITATIONS The median straight-line distance between the racecourse and the local meteorological observatory was 14.2 km (range, 1.1-28.3 km). There was a lack of objective criteria of EHI due to the retrospective nature of the study. CONCLUSIONS We identified specific risk factors for EHI in racehorses. These results may be useful to the equine industry for reducing EHI occurrence in racehorses.
Collapse
Affiliation(s)
- Y Takahashi
- Sports Science Division, Equine Research Institute, Japan Racing Association, Tochigi, Japan
| | - T Takahashi
- Sports Science Division, Equine Research Institute, Japan Racing Association, Tochigi, Japan
| |
Collapse
|
34
|
Soroko M, Śpitalniak-Bajerska K, Zaborski D, Poźniak B, Dudek K, Janczarek I. Exercise-induced changes in skin temperature and blood parameters in horses. Arch Anim Breed 2019; 62:205-213. [PMID: 31807631 PMCID: PMC6852865 DOI: 10.5194/aab-62-205-2019] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2018] [Accepted: 03/27/2019] [Indexed: 12/02/2022] Open
Abstract
The aim of the study was to assess the effects of
training on haematological and biochemical blood parameters as well as on
the changes in body surface temperature in horses. In order to identify the
predictive value of surface temperature measurements as a marker of animal's
performance, their correlations with blood parameters were investigated. The
study was carried out on nine horses divided into two groups: routinely ridden
and never ridden. Infrared thermography was used to assess surface
temperature changes before (BT) and just after training (JAT) on a
treadmill. Seven regions of interest (ROIs) located on the neck, shoulder,
elbow, back, chest, gluteus and quarter were analysed. The blood samples
were taken BT, JAT and 30 min after training (30AT). Haematological
parameters including white blood cells, lymphocytes (LYMs), monocytes (MONOs),
granulocytes (GRAs), eosinophils (EOSs), haematocrit (HCT) and platelets (PLTs)
as well as biochemical parameters such as glucose (GLUC), urea,
Na+, K+ and Ca2+, and creatine phosphokinase (CPK) were
analysed. Our results indicated a significant increase in surface
temperature JAT (p=0.043) in the neck, shoulder, elbow, gluteus and
quarter in routinely ridden horses. Significant changes in EOS (p=0.046)
and HCT (p=0.043) in the case of the never-ridden and routinely ridden group,
respectively, were found between the times of blood collection. In addition,
there was a significant effect of the horse group and the time of blood
collection on the CPK activity (p=0.025 to p=0.045) and urea
concentrations (p=0.027 to p=0.045). In the routinely ridden horses,
there were significant correlations between the changes in MONO
(ρ=0.40), GRA (ρ=-0.40), PLT (ρ=-0.77), HCT (ρ=-0.36), GLUC
(ρ=0.56) and urea (ρ=0.56) and the total ROI temperature changes.
Moreover, significant correlations between the changes in MONO
(ρ=-0.86), EOS (ρ=-0.65), GLUC (ρ=0.85), urea (ρ=0.85),
Na+ (ρ=0.59) and K+ (ρ=-0.85) and the total ROI
temperature changes were found in never-ridden horses. Different changes in
body surface temperature and blood parameters in routinely ridden and
never-ridden horses could be associated with different conditioning and
performance. A significantly higher surface temperature in routinely ridden
horses, as well as the dynamics of changes in HCT, CPK and urea after
training indicate better performance of these horses. Significant
correlations between MONO, GLUC, and urea and a total ROI surface temperature
as well as a negative correlation between MONO and the total ROI temperature
in never-ridden horses indicated poor performance.
Collapse
Affiliation(s)
- Maria Soroko
- Department of Horse Breeding and Equestrian Studies, Wroclaw University of Environmental and Life Sciences, Wrocław, 50-375, Poland
| | - Kinga Śpitalniak-Bajerska
- Department of Environmental Hygiene and Animal Welfare, Wroclaw University of Environmental and Life Sciences, Wrocław, 50-375, Poland
| | - Daniel Zaborski
- Department of Ruminants Science, West Pomeranian University of Technology, Szczecin, 71-270, Poland
| | - Błażej Poźniak
- Department of Pharmacology and Toxicology, Wroclaw University of Environmental and Life Sciences, Wrocław, 50-375, Poland
| | - Krzysztof Dudek
- Faculty of Mechanical Engineering, Wroclaw University of Technology, Wrocław, 50-370, Poland
| | - Iwona Janczarek
- Department of Horse Breeding and Use, University of Life Sciences in Lublin, Lublin, 20-950, Poland
| |
Collapse
|
35
|
Affiliation(s)
- J. Steinhoff-Wagner
- Animal Nutrition, Institute of Animal Science, University of Bonn, Bonn, Germany
| |
Collapse
|
36
|
Stephens-Brown L, Davis M. Water requirements of canine athletes during multi-day exercise. J Vet Intern Med 2018; 32:1149-1154. [PMID: 29572954 PMCID: PMC5980383 DOI: 10.1111/jvim.15091] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 01/02/2018] [Accepted: 02/05/2018] [Indexed: 11/29/2022] Open
Abstract
BACKGROUND Exercise increases water requirements, but there is little information regarding water loss in dogs performing multi-day exercise OBJECTIVES: Quantify the daily water turnover of working dogs during multi-day exercise and establish the suitability of SC administration of tracer to determine water turnover. ANIMALS Fifteen privately owned Labrador retrievers trained for explosive detection duties and 16 privately owned Alaskan Huskies conditioned for mid-distance racing. METHODS All dogs received 0.3 g D2 O/kg body weight by IV infusion, gavage, or SC injection before the start of a multi-day exercise challenge. Explosive detection dogs conducted 5 days of simulated off-leash explosive detection activity. Alaskan sled dogs completed a mid-distance stage race totaling 222 km in 2 days. Total body water (TBW) and daily water turnover were calculated using both indicator dilution and elimination regression techniques. RESULTS Total body water (% of body weight) varied from 60% ± 8.6% in minimally conditioned Labrador retrievers to 74% ± 4.5% in highly conditioned Labrador retrievers. Daily water turnover was as high as 45% of TBW during exercise in cold conditions. There was no effect of sex or speed on daily water turnover. There was good agreement between results calculated using the indicator dilution approach and those calculated using a semilog linear regression approach when indicator isotope was administered IV or SC. CONCLUSIONS AND CLINICAL IMPORTANCE Water requirements are influenced primarily by the amount of work done. SC administration of isotope-labeled water offers a simple and accurate alternative method for metabolic studies.
Collapse
Affiliation(s)
- Lara Stephens-Brown
- College of Veterinary Medicine, University of Minnesota, St. Paul, Minneapolis, Minnesota
| | - Michael Davis
- Department of Physiological Sciences, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, Oklahoma
| |
Collapse
|
37
|
|
38
|
Verdegaal ELJMM, Delesalle C, Caraguel CGB, Folwell LE, McWhorter TJ, Howarth GS, Franklin SH. Evaluation of a telemetric gastrointestinal pill for continuous monitoring of gastrointestinal temperature in horses at rest and during exercise. Am J Vet Res 2017. [DOI: 10.2460/ajvr.78.7.778] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
|
39
|
Current Knowledge of Pathologic Mechanisms and Derived Practical Applications to Prevent Metabolic Disturbances and Exhaustion in the Endurance Horse. J Equine Vet Sci 2017. [DOI: 10.1016/j.jevs.2016.12.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
|
40
|
McNicholl J, Howarth GS, Hazel SJ. Influence of the Environment on Body Temperature of Racing Greyhounds. Front Vet Sci 2016; 3:53. [PMID: 27446941 PMCID: PMC4927620 DOI: 10.3389/fvets.2016.00053] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2016] [Accepted: 06/17/2016] [Indexed: 01/04/2023] Open
Abstract
Heat strain is a potential risk factor for racing greyhounds in hot climates. However, there have been limited studies into the incidence of heat strain (when excess heat causes physiological or pathological effects) in racing greyhounds. The aim of this study was to determine if heat strain occurs in racing greyhounds, and, if so, whether environmental factors (e.g., ambient temperature and relative humidity) or dog-related factors (e.g., sex, bodyweight, color) are associated with the risk of heat strain. A total of 229 greyhounds were included in over 46 race meetings and seven different race venues in South Australia, Australia. Rectal temperatures of dogs were measured pre- and postrace and urine samples collected for analysis of myoglobinuria. Ambient temperature at race times ranged between 11.0 and 40.8°C and relative humidity ranged from 17 to 92%. There was a mean increase in greyhound rectal temperature of 2.1°C (range 1.1-3.1°C). A small but significant association was present between ambient temperature and increase in rectal temperature (r (2) = 0.033, P = 0.007). The mean ambient temperature at race time, of dogs with postrace rectal temperature of or exceeding 41.5°C, was significantly greater than at race time of dogs with a postrace rectal temperature ≤41.5°C (31.2 vs. 27.3°C, respectively, P = 0.004). When the ambient temperature reached 38(o)C, over one-third (39%) of dogs had a rectal temperature >41.5°C. Over half of postrace urine samples were positive by Dipstick reading for hemoglobin/myoglobin, and of 77 urine samples positive for Dipstick readings, 95% were positive for myoglobin. However, urinary myoglobin levels were not associated with ambient temperature or postrace rectal temperatures. The mean increase in rectal temperature was greater in dark (black, blue, brindle) than light (fawn and white) colored greyhounds. The results suggest heat strain occurs in racing greyhounds, evidenced by postrace rectal temperatures over 41.5°C and postrace myoglobinuria. Risk of heat strain may be increased in higher ambient temperatures and in darker colored greyhounds. Further research into the incidence of heat strain in racing greyhounds, and longer term physiological responses to heat strain, are warranted.
Collapse
Affiliation(s)
- Jane McNicholl
- School of Animal and Veterinary Sciences, University of Adelaide , Adelaide, SA , Australia
| | - Gordon S Howarth
- School of Animal and Veterinary Sciences, University of Adelaide , Adelaide, SA , Australia
| | - Susan J Hazel
- School of Animal and Veterinary Sciences, University of Adelaide , Adelaide, SA , Australia
| |
Collapse
|
41
|
Brownlow MA, Dart AJ, Jeffcott LB. Exertional heat illness: a review of the syndrome affecting racing Thoroughbreds in hot and humid climates. Aust Vet J 2016; 94:240-7. [DOI: 10.1111/avj.12454] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2015] [Revised: 01/28/2016] [Accepted: 03/22/2016] [Indexed: 12/01/2022]
Affiliation(s)
- MA Brownlow
- Barkers Lodge Road; Picton New South Wales Australia
| | - AJ Dart
- Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden; University of Sydney; 410 Werombi Road Camden New South Wales, 2570 Australia
| | - LB Jeffcott
- Research and Clinical Trials Unit, University Veterinary Teaching Hospital Camden; University of Sydney; 410 Werombi Road Camden New South Wales, 2570 Australia
| |
Collapse
|
42
|
Curtin NA, Diack RA, West TG, Wilson AM, Woledge RC. Skinned fibres produce the same power and force as intact fibre bundles from muscle of wild rabbits. ACTA ACUST UNITED AC 2015. [PMID: 26206354 DOI: 10.1242/jeb.121897] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Skinned fibres have advantages for comparing the muscle properties of different animal species because they can be prepared from a needle biopsy taken under field conditions. However, it is not clear how well the contractile properties of skinned fibres reflect the properties of the muscle fibres in vivo. Here, we compare the mechanical performance of intact fibre bundles and skinned fibres from muscle of the same animals. This is the first such direct comparison. Maximum power and isometric force were measured at 25 °C using peroneus longus (PL) and extensor digiti-V (ED-V) muscles from wild rabbits (Oryctolagus cuniculus). More than 90% of the fibres in these muscles are fast-twitch, type 2 fibres. Maximum power was measured in force-clamp experiments. We show that maximum power per volume was the same in intact (121.3 ± 16.1 W l(-1), mean ± s.e.m.; N=16) and skinned (122.6 ± 4.6 W l(-1); N=141) fibres. Maximum relative power (power/F(IM) Lo, where F(IM) is maximum isometric force and Lo is standard fibre length) was also similar in intact (0.645 ± 0.037; N=16) and skinned (0.589 ± 0.019; N=141) fibres. Relative power is independent of volume and thus not subject to errors in measurement of volume. Finally, maximum isometric force per cross-sectional area was also found to be the same for intact and skinned fibres (181.9 kPa ± 19.1; N=16; 207.8 kPa ± 4.8; N=141, respectively). These results contrast with previous measurements of performance at lower temperatures where skinned fibres produce much less power than intact fibres from both mammals and non-mammalian species.
Collapse
Affiliation(s)
- Nancy A Curtin
- Structure and Motion Laboratory, Royal Veterinary College, University of London, Hawkshead Lane, Hatfield AL9 7TA, UK National Heart and Lung Institute, Imperial College London, London SW7 2AZ, UK
| | - Rebecca A Diack
- Structure and Motion Laboratory, Royal Veterinary College, University of London, Hawkshead Lane, Hatfield AL9 7TA, UK
| | - Timothy G West
- Structure and Motion Laboratory, Royal Veterinary College, University of London, Hawkshead Lane, Hatfield AL9 7TA, UK
| | - Alan M Wilson
- Structure and Motion Laboratory, Royal Veterinary College, University of London, Hawkshead Lane, Hatfield AL9 7TA, UK
| | - Roger C Woledge
- Structure and Motion Laboratory, Royal Veterinary College, University of London, Hawkshead Lane, Hatfield AL9 7TA, UK
| |
Collapse
|
43
|
Affiliation(s)
- Robert J. Collier
- School of Animal and Comparative Biomedical Science, University of Arizona, Tucson, Arizona 85719;
| | - Kifle G. Gebremedhin
- Department of Biological and Environmental Engineering, Cornell University, Ithaca, New York 14853
| |
Collapse
|
44
|
Stefánsdóttir GJ, Ragnarsson S, Gunnarsson V, Jansson A. Physiological response to a breed evaluation field test in Icelandic horses. Animal 2014; 8:431-9. [PMID: 24387835 PMCID: PMC3942816 DOI: 10.1017/s1751731113002309] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2013] [Accepted: 11/28/2013] [Indexed: 11/07/2022] Open
Abstract
This study examined the response in terms of heart rate (HR), respiratory rate (RR), haematocrit (Htc), rectal temperature (RT), and some plasma variables in Icelandic horses of different sexes and ages performing the riding assessment in a breed evaluation field test (BEFT). The study was conducted in Iceland on 266 horses (180 mares and 86 stallions, divided into four age groups; 4, 5, 6 and ≥7 years old). RT and RR were recorded and blood samples were taken before the warm-up and after the riding assessment. Horse HR, velocity and distance were recorded during the warm-up, the riding assessment and a 5-min recovery period. The distance covered in the BEFT was 2.9 ± 0.4 km (range: 1.8 to 3.8 km, n=248), the duration was 9:37 ± 1:22 min:s (range: 5:07 to 15:32 min:s, n=260) and the average speed was 17.8 ± 1.4 km/h (range: 13.2 to 21.3 km/h, n=248). Average HR was 184 ± 13 b.p.m. (range: 138 to 210 b.p.m., n=102) and peak HR 224 ± 9 b.p.m. (range: 195 to 238 b.p.m., n=102), and 36% of the BEFT was performed at HR ≥200 b.p.m. Post-exercise plasma lactate concentration (Lac) was 18.0 ± 6.5 mmol/l (range: 2.1 to 34.4 mmol/l, n=266), and there was an increase in total plasma protein, plasma creatine kinase and aspartate amino transferase concentration, as well as RR, RT and Htc. Stallions covered a longer total distance (in the warm-up and BEFT) (P<0.05), at a faster speed during BEFT (P<0.001) than mares and had higher Htc and lower HR and post-exercise Lac values. There were few effects of age, but the 4- and 5-year-old horses had lower Htc than older horses and 4-year-old horses had higher post-exercise RR than older horses, although they were ridden for a shorter distance, shorter duration and at lower peak velocity (P<0.1). The results showed that the riding assessment in the BEFT is a high-intensity exercise. The results also showed that aerobic fitness was higher in stallions and that age had a limited effect on the physiological response. It is suggested that these results should be used as a guide for the development of training programmes and fitness tests in Icelandic horses that would improve both performance and welfare of the horse.
Collapse
Affiliation(s)
- G. J. Stefánsdóttir
- Department of Equine Science, Hólar University College, 551 Sauðárkrókur, Iceland
- Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, P.O. Box 7024, 750 07 Uppsala, Sweden
| | - S. Ragnarsson
- Department of Equine Science, Hólar University College, 551 Sauðárkrókur, Iceland
| | - V. Gunnarsson
- Department of Equine Science, Hólar University College, 551 Sauðárkrókur, Iceland
| | - A. Jansson
- Department of Equine Science, Hólar University College, 551 Sauðárkrókur, Iceland
- Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, P.O. Box 7024, 750 07 Uppsala, Sweden
| |
Collapse
|
45
|
McKenzie E, Esser M, Payton M. Serum biochemistry changes in horses racing a multiday endurance event. COMPARATIVE EXERCISE PHYSIOLOGY 2014. [DOI: 10.3920/cep140017] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Endurance competition frequently provokes serum biochemistry alterations in horses racing single day events. This study assessed the effect of consecutive days of endurance racing on commonly analysed serum biochemistry variables of horses. Blood was obtained once before 54 horses commenced racing 40 km or 80 km/day, and 4-6 h after horses finished each day of racing. Data were analysed via repeated measures ANOVA (P<0.05, mean ± standard error). Ten horses completed 40 km once, and 44, 18 and 9 horses completed one, two and three consecutive 80 km days, respectively, with valid results obtained for 41 of the 44 horses. Before racing, all variables were within reference intervals in both groups. After one day of racing, serum urea nitrogen and magnesium were higher in horses racing 80 km compared to 40 km, and total CO2 was lower. In both groups, total protein and globulin decreased after racing, and creatine kinase increased, exceeding the reference interval in the 80 km group on day one and two of racing. Within the 80 km group, serum urea nitrogen, creatinine, phosphorus and bilirubin were slightly higher on all race days than before racing, and serum glucose exceeded reference interval on day one of racing. Serum albumin was slightly lower on day two and three of racing, and aspartate transaminase was higher and exceeded reference interval on all race days. No significant changes occurred in sodium, potassium, chloride, calcium or magnesium concentrations in either category. Subset analysis of valid results from six horses that raced three consecutive 80 km days revealed similar changes in serum urea nitrogen, phosphorus, total protein, albumin, globulin, and muscle enzymes with racing. This study identified mild serum biochemistry changes in horses racing 80 km/day for up to three consecutive days, suggesting that non-elite multiday endurance competition is well tolerated.
Collapse
Affiliation(s)
- E.C. McKenzie
- Department of Clinical Sciences, College of Veterinary Medicine, Oregon State University, 700 SW 30th Street, Corvallis, OR 97331, USA
| | - M.M. Esser
- Department of Clinical Sciences, College of Veterinary Medicine, Oregon State University, 700 SW 30th Street, Corvallis, OR 97331, USA
- University of Minnesota Saint Paul, Room 225 VMC, 1365 Gortner Ave, St Paul, MN 55108, USA
| | - M.E. Payton
- Department of Statistics, Oklahoma State University, 301 MSCS, Stillwater, OK 74078, USA
| |
Collapse
|
46
|
Abstract
Evolutionary forces drive beneficial adaptations in response to a complex array of environmental conditions. In contrast, over several millennia, humans have been so enamored by the running/athletic prowess of horses and dogs that they have sculpted their anatomy and physiology based solely upon running speed. Thus, through hundreds of generations, those structural and functional traits crucial for running fast have been optimized. Central among these traits is the capacity to uptake, transport and utilize oxygen at spectacular rates. Moreover, the coupling of the key systems--pulmonary-cardiovascular-muscular is so exquisitely tuned in horses and dogs that oxygen uptake response kinetics evidence little inertia as the animal transitions from rest to exercise. These fast oxygen uptake kinetics minimize Intramyocyte perturbations that can limit exercise tolerance. For the physiologist, study of horses and dogs allows investigation not only of a broader range of oxidative function than available in humans, but explores the very limits of mammalian biological adaptability. Specifically, the unparalleled equine cardiovascular and muscular systems can transport and utilize more oxygen than the lungs can supply. Two consequences of this situation, particularly in the horse, are profound exercise-induced arterial hypoxemia and hypercapnia as well as structural failure of the delicate blood-gas barrier causing pulmonary hemorrhage and, in the extreme, overt epistaxis. This chapter compares and contrasts horses and dogs with humans with respect to the structural and functional features that enable these extraordinary mammals to support their prodigious oxidative and therefore athletic capabilities.
Collapse
Affiliation(s)
- David C Poole
- Departments of Kinesiology, Anatomy and Physiology, Kansas State University, Manhattan, KS, USA.
| | | |
Collapse
|
47
|
Tofé E, Muñoz A, Castejón F, Trigo P, Castejón-Riber C, Gómez-Díez M, Riber C. Behavior of renin angiotensin aldosterone axis during pulling exercises in euhydrated and dehydrated horses. Res Vet Sci 2013; 95:616-22. [DOI: 10.1016/j.rvsc.2013.02.012] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2012] [Revised: 02/22/2013] [Accepted: 02/24/2013] [Indexed: 11/25/2022]
|
48
|
Rhoads RP, Baumgard LH, Suagee JK. 2011 and 2012 Early Careers Achievement Awards: metabolic priorities during heat stress with an emphasis on skeletal muscle. J Anim Sci 2013; 91:2492-503. [PMID: 23408824 DOI: 10.2527/jas.2012-6120] [Citation(s) in RCA: 54] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/28/2023] Open
Abstract
Environmental heat stress undermines efficient animal production resulting in a significant financial burden to agricultural producers. The reduction in performance during heat stress is traditionally thought to result from reduced nutrient intake. Recently, this notion has been challenged with observations indicating that heat-stressed animals may exploit novel homeorhetic strategies to direct metabolic and fuel selection priorities independent of nutrient intake or energy balance. Alterations in systemic physiology support a shift in metabolism, stemming from coordinated interactions at whole-body and tissue-specific levels. Such changes are characterized by increased basal and stimulated circulating insulin concentration in addition to the ostensible lack of basal adipose tissue lipid mobilization coupled with reduced adipocyte responsiveness to lipolytic stimuli. Hepatic and skeletal muscle cellular bioenergetics also exhibit clear differences in carbohydrate production and use, respectively, due to heat stress. The apparent dichotomy in intermediary metabolism between the 2 tissue types may stem from factors such as tricarboxylic acid cycle substrate flux and mitochondrial respiration. Thus, the heat stress response markedly alters postabsorptive carbohydrate, lipid, and protein metabolism through coordinated changes in fuel supply and use across tissues in a manner that is distinct from commonly recognizable changes that occur in animals on a reduced plane of nutrition. Perhaps most intriguing is that the coordinated systemic, cellular, and molecular changes appear conserved across physiological states and among different ruminant and monogastric species. Ultimately, these changes result in the reprioritization of skeletal muscle fuel selection during heat stress, which may be important for whole-body metabolism and overall physiological adaptation to hyperthermia.
Collapse
Affiliation(s)
- R P Rhoads
- Department of Animal and Poultry Sciences, Virginia Tech, Blacksburg 24061, USA.
| | | | | |
Collapse
|
49
|
Murase H, Sakai S, Kusano K, Hobo S, Nambo Y. Serum zinc levels and their relationship with diseases in racehorses. J Vet Med Sci 2013; 75:37-41. [PMID: 22972467 DOI: 10.1292/jvms.12-0122] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Zinc is one of the essential microelements involved in the regulation of enzyme activity, as well as metabolism of nucleic acid and proteins. There have been few reports on equine serum zinc concentrations during the training period, and little is known about the relationship between zinc levels and diseases in horses. In this study, we measured serum zinc levels in healthy Thoroughbred racehorses, as well as in other horses, under general disease or training conditions. The reference value for serum zinc levels in Thoroughbred horses was 41-79 μg/dl. There were no differences in serum zinc levels due to sex or age. Significant decreases in serum zinc levels were observed after training, but serum zinc levels did not vary with intensity of sweating. Serum zinc levels were lower in horses clinically diagnosed as having shipping fever (36.3 ± 2.7 μg/dl), fever (45.3 ± 3.0 μg/dl) and cellulitis (44.0 ± 3.4 μg/dl), as compared to control values (59.7 ± 9.7 μg/dl). They also tended to decrease in experimentally infected horses one day after inoculation. Changes in serum zinc levels reached nadir one day after surgical invasion, except for a horse that experienced complicating shock. These results suggest that zinc is a serological indicator of inflammatory status in Thoroughbred horses.
Collapse
Affiliation(s)
- Harutaka Murase
- Equine Science Division, Hidaka Training and Research Center, Japan Racing Association, 535-13 Nishicha, Hokkaido 057-0171, Japan
| | | | | | | | | |
Collapse
|
50
|
Jansson A, Johannisson A, Kvart C. Plasma aldosterone concentration and cardiovascular response to low sodium intake in horses in training. Equine Vet J 2011:329-34. [PMID: 21059026 DOI: 10.1111/j.2042-3306.2010.00244.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
REASON FOR PERFORMING THE STUDY Horses in training lose large amounts of sodium but little is known about the cardiovascular response to low sodium intake. OBJECTIVES To investigate the effect of low sodium intake on plasma aldosterone (pAldo) concentrations and the cardiovascular system of athletic horses, and to identify markers of low sodium intake. METHODS Seven Standardbred geldings in training (trained twice a week) were randomly offered a standardised diet supplemented (NaS, 58 mg Na/kg bwt) and not supplemented (NaN, 3 mg Na/kg bwt) with NaCl for 5 weeks in a changeover design. Blood samples were taken once a week and in Week 5, before and following an exercise test until 22.30 h and analysed for blood sodium (bNa), total plasma protein (TPP), pAldo, troponin I and packed cell volume (PCV). Blood pressure (BP) was measured and pulse wave recorded at rest with high definition oscillometric-technique (HDO). ECG and echocardiography were recorded. Water intake was measured before and on the day of exercise and voluntary saline intake was measured for 2 days after each period. Faecal samples were taken weekly and analysed for sodium and potassium content. RESULTS The pAldo and the PCV was higher in NaN compared to NaS. There were no differences between diets in BP, ECG, plasma troponin I and echocardiogram but HDO pulse amplitude tended to be smaller on diet NaN. Water intake was lower on diet NaN and saline intake higher. The response to exercise in bNa, pAldo, PCV and TPP was different on the 2 diets. Faecal potassium/sodium ratio was higher on NaN than on NaS. CONCLUSION This study shows that 5 weeks of low sodium intake increased plasma aldosterone concentration and PCV but no alterations in heart function was observed. Faecal potassium/sodium ratio could be used to assess sodium status in horses.
Collapse
Affiliation(s)
- A Jansson
- Department of Animal Nutrition and Management, Swedish University of Agricultural Sciences, Uppsala, Sweden.
| | | | | |
Collapse
|